After using DaSyLab for 8 yrs. I am now trying to work with Labview 8.5 and the biggest hurdle I am trying to overcome is the different "terminology" of the two.

I have set up a basic NI-DAQ system (in this case using a PCI-6071E card). I set up the DAQ Assistant for "Continuous Samples" at 100 samples to read and at a rate of 300HZ. I am scanning 2 channels and coming out of the DAQ Assist through a Filter and from there to simple digital meters on the front panel. All this seems to work OK.

I am trying to record data from 2 channels in the "Write to Measurement File" as text and 1 file. Reading this data in Excel works well except in no time I have a large file...as would be expected.

In DaSyLab there is a module called a "Seperate" module. If the DAQ hardware is running at 300 Hz you can tell the module to take 1 sample at start.....skip 2999 samples and then take 1 sample....and do this continuously. This gives you a "sample record" rate of 1 sample every 10 seconds and comes out in a "very manageable" single ASCI file in Excel over a length of time. As I run testing on various equipment and components....1 test may go for days on many channels, so this sampling rate is a definite need.

I have hunted and searched for days now in Labview and on the internet and cannot find what I am looking for. Can someone steer me to the .VI or whatever it is that I need to accomplish the data reduction?? I can't believe this should be this complicated....but I think the terminology I am used to is not matching the terminology I need to know.

Any help is greatly appreciated and thanks in advance!!

I don't have experience with the Write to Measurement File VI (most professional developers avoid using Express VIs for most things), but here's one simplistic option of how this can be done:



If this doesn't help you, you should upload the code you already have.

Thanks for the reply and suggestion.....but.....

Somehow I'm thinking if Labview is using the "dynamic data" VI's....there should be a quick way to reduce the amount of data being sent to the Write to Meas. file. Hopefully I can figure it out...

I'll upload the VI that I'm working with....and it is very basic and probably crude....to say the least....

I have zero experience with the dynamic data type and the express VIs it uses, so I can't really help you, but the VIs in the Express>>Signal Manipulation palette should help you.

Specifically, you can use the conversion VIs on the bottom to convert to a 2D array and get the data you need out of that and then convert back, but the sample compression VI might also do what you want.